Is it too bright or is it high resolution?

I have always liked the "bright" highs, but I interpreted them as detailed. But as I aged, I find that my tastes have changed. Not wanting to dull the highs but to have the detail without the "Schrill" or piercing. I have begun looking to replace my Revel Performa F32's and am looking to gain a more balanced sound without drawing so much attention to the highs as in your face. I am sure my hearing is diminished over the past 30 years or so, although a recent hearing test, the Dr said I still had exceptional hearing for a man much younger. But he did say I am missing some mid to high frequencies. So my point, Phd, is maybe your listening habits have changed and might be part of what you're experiencing. One last thought, I have a good CD player and a few years back it seemed too bright and I changed cables. This made a significant difference in taming that "schrillness" for the lack of a better word.

Is it too bright or is it high resolution?

Yes.

The answer is in the ear of the beholder.
There is a very fine line between high definition and too bright.
You will know it when you cross it. You will find that your listening sessions growing shorter as listening fatigue begins to set in sooner and sooner.

While I do enjoy high definition, I do realize that one can go too far.
I have heard systems that have reached the point of sterile, amusical, and uninvolving.

Decades ago TAS had an anecdote about an audiophile who goes to a live symphony concert and turns to his companion and asks, "where are all the high frequencies?"

Too bright being high resolution is a generalization. To get high resolution, you need a system where the source and amp can actually reproduce the fine detail, and then speakers that can deliver it as well.  Many budget and vintage speakers simply can not.

One can have a harsh/bright sounding system that can't reproduce fine detail.

Too bright being high resolution is a generalization ...
One can have a harsh/bright sounding system that can't reproduce fine detail

I agree completely. There's no inherent link between brightness and resolution. In fact, some of the highest-res recordings I have - the ones that are filled with detail and nuance - aren't bright at all. They may be extended on top, but never bright. Brightness is actually often the result of distortion, not detail.